1 onion, diced
500g/1lb 2oz plums, stoned and roughly chopped
salt and freshly ground black pepper
75g/3oz caster sugar
Β½ tsp ground cinnamon
3 tbsp olive oil
2 tsp sesame seeds
1 star anise
50ml/2fl oz malt vinegar
4 balls buffalo mozzarella, drained and cut into quarters
8 slices Parma ham, cut in half lengthways
8 slices ciabatta